The nodulation (nod) genes are classified as common nod genes or host specific nod genes. Some statements related to such classification are given below;

a) nod A is a common nod gene and nod Q is a host specific gene

b) nod B is a common nod gene and nod C is a host specific gene

c) nod C is a common nod gene and nod H is a host specific gene

d) nod H is a common nod gene and nod P is a host specific gene

Choose the correct answer from the above statements:

#Question id: 11583

#Unit 7. System Physiology – Animal

Use the figure to answer the following question.

In an experiment, rats' ovaries were removed immediately after impregnation, and then the rats were divided into two groups. Treatments and results are summarized in the table. The results most likely occurred because progesterone exerts an effect on the ________.

#Question id: 11584

#Unit 7. System Physiology – Animal

Use the bar graph to answer the following question.

People who suffer from chronic fatigue syndrome (CFS) experience ongoing, debilitating fatigue. In one study, cortisol levels in the saliva during the first hour after waking were measured and compared between CFS patients and people without CFS (controls). The data is summarized in the graph. What can you infer from the data?

#Question id: 11585

#Unit 7. System Physiology – Animal

Osteoporosis is a condition in which the density of bones is decreased so much that the individual is at a higher risk of fractures. The more calcium in the bones, the better the bone density. Which of the following would produce the greatest increase in bone calcium levels?

#Question id: 11586

#Unit 7. System Physiology – Animal

Predict the effects of a drug that increases adrenocorticotropic hormone (ACTH) synthesis.

#Question id: 11587

#Unit 7. System Physiology – Animal

People experiencing chronic stress may be more likely to become sick because ________.

#Question id: 11588

#Unit 7. System Physiology – Animal

Correct and appropriate signal transduction processes are generally under strong selective pressure and are determined by the properties of the molecules involved, the concentrations of signal and receptor molecules, and the binding affinities between signal and receptor. Therefore, a hormone action is very specific in a species at any one point in time. However, there are examples of very diverse functions of a specific hormone between groups of organisms. For example, thyroxin, which is produced in all vertebrates and many invertebrates, can trigger growth, differentiation, metamorphosis, maturation, reproduction, behavior, temperature tolerance, osmoregulation, or seasonal adaptation depending on the organism in which it is produced. What is the most logical explanation for such different responses triggered by thyroxin in organisms?